<!DOCTYPE html>
<html lang='en'>
<head>
    <meta charset='UTF-8'>
    <meta name='viewport' content='width=device-width, initial-scale=1.0'>
    <title>Document</title>
    <script type='text/javascript' src='js/vue.js'></script>
</head>
<body>
    <div id='app'>
        {{msg}}

        <input type="button" @click='btn' value='点击if&show'>
        <p v-if='flag'>if====让我显示或者隐藏</p>
        <p v-show='!flag'>show=====让我显示或者隐藏</p>

        ========
        <ul>
            <li v-if='score<60'>不及格</li>
            <li v-else-if='score<70'>及格</li>
            <li v-else>优秀</li>
            <span></span>
        </ul>
    </div>
    <script type='text/javascript'>
    
        var vm = new Vue({
            el: '#app',
            data: {
                msg: 'Hello Vue',
                flag:false,
                score:51
            },
            methods:{
                btn(){
                    this.flag=!this.flag

                }
            }
        });
    </script>
</body>
</html>